This essay explains how Arthurian legends and current movies, like Spiderman, all use the motif of Concealing Identities.

Arthur Revisited: Concealed Identities
Everybody's wanted to be somebody else some time or the other in their life. Why do people want to be somebody else? What is it about hiding behind a mask and concealing your identity that is so appealing that it is featured in works of literature from a 15th century medieval story by Sir Thomas Mallory, to a 20th century retelling of the Arthurian legend by T.H. White, to a modern blockbuster film adaptation of the Marvel comic superhero Superman? Whatever it is, it's enough to be used over and over again as a timeless motif that has been and will…